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Biomedical subjects

T Nishihara

Publications and source records attributed to T Nishihara.

At least 253 records · Page 14Linked to original sources
PubMed1985

Synthesis and deposition of spore coat proteins during sporulation of Bacillus megaterium.

Rabbit (anti-spore coat protein) IgG was prepared by immunization with coat proteins extracted with sodium dodecyl sulfate and dithiothreitol from isolated spore coats of Bacillus megaterium ATCC 12872. Coat proteins were detected from 3 hr after the end of exponential growth (t3) in the mother cell cytoplasmic fraction by sandwich enzyme immunoassay using this antibody. The proteins in the forespore coat protein fraction increased from t3 and reached a plateau at t10. Immunoblot analysis for the coat proteins in sporulating cells revealed the sequential synthesis of various proteins in the mother cell cytoplasmic fraction and simultaneous deposition of the same proteins as in the forespore coat fraction. These results suggest that turnover of precursor proteins of the spore coat is very rapid if precursor proteins are produced and they are proteolytically processed to produce mature proteins. Specific antibody to the 48,000-dalton protein, which is a major protein, did not cross-react with any other major (36,000, 22,000, 19,500, and 17,500-dalton) proteins. Specific antibody to the 22,000-dalton protein did not cross-react with the 48,000, 36,000, 19,500, 17,500, and 16,000-dalton proteins, but did cross-react with the 44,000, 25,000, and 12,000-dalton proteins.

Animals↗
PubMed1985

Biochemical and immunobiological properties of lipopolysaccharide (LPS) from Bacteroides gingivalis and comparison with LPS from Escherichia coli.

Lipopolysaccharides (LPSs) were isolated from Bacteroides gingivalis and Escherichia coli by the phenol-water and butanol-water procedures. The phenol-water-extracted LPS from B. gingivalis 381 was composed of 46% carbohydrate, 23% hexosamine, 18% fatty acid, and 5% protein. The major component sugars of this preparation were glucose, glucosamine, rhamnose, galactose, galactosamine, and mannose, and their molecular ratio was 1:0.9:0.7:0.6:0.6:0.4, respectively. Neither heptose nor 2-keto-3-deoxyoctonate was detected. The butanol-water-extracted LPS from this strain was composed of 76% glucose, 7% fatty acid, and 13% protein, and it was associated with a number of polypeptides (13 to 56 kilodaltons). The main fatty acid of both LPS preparations was palmitic acid. It was found that biological activities of LPS from B. gingivalis were comparable to those of LPS from E. coli in terms of activation of the clotting enzyme of Limulus amebocyte lysate, mitogenicity, polyclonal B cell activation, and stimulation of interleukin 1 production in BALB/c mice. Furthermore, LPS-nonresponsive C3H/HeJ spleen cells were found to yield good mitogenic responses to both phenol-water-extracted LPS and butanol-water-extracted LPS from B. gingivalis or butanol-water-extracted LPS from E. coli. On the other hand, spleen cells from LPS-responsive C3H/HeN mice responded well to all these LPS preparations.

Amino Acids↗
PubMed1985

Screening for new antifolates of microbial origin and a new antifolate AM-8402.

A screening method was established for new specific inhibitors of folate metabolism. Culture broths of soil isolates were selected based on relative microbial activity. A culture, to be retained, must be active against Enterococcus faecium grown in a medium which contains a limited amount of pteroic acid but lacks activity against the microorganism grown in a medium supplemented with thymidine. By this screening method, three new antibiotics, diazaquinomycins A and B and AM-8402 were selected from eight thousand soil isolates. The isolation and structures of diazaquinomycins have been reported. AM-8402 is a new antifolate active against Gram-positive bacteria and mycoplasmas. It consists of a nanaomycin D moiety as chromophore and a deoxysugar and is structurally related to medermycin.

Actinomycetales↗
PubMed1985

[Correlation between the growth of transplantable tumors under protein deprivation and intratumoral amino acid concentration].

Nutritional restriction in the diet has a deleterious influence on tissue and transplantable tumor growths. Correlation between the growth of 81 B or MM 48 mammary tumors and intratumoral amino acid concentration was studied in syngeneic C3H/He mice fed a diet with a low (D) or normal (N) protein content. D-mice revealed a relatively longer lag phase than N-mice, but showed almost the same growth curve. Some kinds of amino acid, alanine, valin, glycine, and so on were recognized in D-mice tumors at higher levels more than in N-mice. In protein malnutrition, urea, the final amino acid degradation product, was not detected in the transplanted tumor or muscle of D-mice. The high tissue levels of alanine, glycine and glutamine are undoubtedly related to their participation in many metabolic reactions, so that they are readily and extensively synthesized. We speculate that D-mice would maintain an adequate intratumoral amino acid level through interorgan relationships in order for the transplanted tumor to grow.

Amino Acids↗
PubMed1985

[Fundamental and clinical studies on cefoperazone in pediatrics, with special reference to renal toxicity].

Fundamental, clinical studies on cefoperazone (CPZ), a new synthetic antibiotic of cephalosporins was conducted to obtain results as follows. This preparation, 11.4-50 mg/kg was administered to 11 cases of children by intravenous drip infusion for 30 minutes, and serum levels were studied. The highest serum level at the completion of infusion was 40.0-138.0 mcg/ml. A dose response was observed. The half-life in serum averaged 1.55 hours except 2.4 hours observed with 1 case of liver dysfunction. When the urinary excretion during 30 minutes drip infusion was examined, the urinary recovery rate at 0-6 hours in 2 cases of children averaged 17.2% and was low at 5.3% in 1 case of membranoproliferative glomerulonephritis. In terms of the clinical effect on bacterial infections in pediatric field, CPZ proved effective in all of the 21 cases in which it was used alone. And it showed an excellent antibacterial activity against all the bacteria isolated from cases used as the subjects. When side effects were studied, diarrhea and slight impairment of the liver were observed, but all were transient. As a result of a study on the renal toxicity of CPZ, CPZ was deemed as being a drug which hardly causes disturbance of renal tubules judging from the aspect of the beta-D-N-acetylglucosaminidase activity in urine and variations in the urine beta 2-microglobulin levels.

Adolescent↗
PubMed1984

Extranodal lymphoma terminating in acute leukemia associated with IgD monoclonal gammopathy. A case report.

A case of malignant lymphoma associated with IgD monoclonal gammopathy is described. Orbital and testicular tumors were observed, while peripheral lymphadenopathy was absent. Neoplastic lymphoid cells appeared in peripheral blood, bone marrow, and pleural effusion with progression of the disease. Analysis of the serum suggested "unreactive" light chain determinants in monoclonal protein. In immunohistochemical studies and in vitro experiments, it was confirmed that IgD monoclonal gammopathy was directly related to the neoplastic cells. These unusual findings suggest that neoplastic changes such as neoplasms of other B-cell systems may occur at various stages in the differentiation and maturation of IgD-forming B-cell lineage.

Acute Disease↗
PubMed1984

Antigen-independent leukocyte random locomotion inhibitory activity in human ultrafiltrated leukocyte extracts.

Human ultrafiltrated leukocyte extracts (MW less than 5000) were fractionated by Sephadex G-10 column chromatography and the effects of these fractions on leukocyte random locomotion were investigated in vitro. Fr-4, one of these fractions, had significant leukocyte random locomotion inhibitory activity, independent of the presence of mononuclear leukocytes. This inhibitory activity was not due to cytotoxic effects on leukocytes. As seen by scanning electron microscopy, the number of cell surface pseudopods on leukocytes incubated with Fr-4 was reduced. Fr-4A, one of three fractions separated from Fr-4 by Sephadex G-25 column chromatography, significantly inhibited leukocyte random locomotion. Fr-4A contained numerous components, one of which was identified as 2-deoxyribose, on the basis of thin-layer chromatography. Biologically 2-deoxyribose showed an inhibitory effect on leukocyte locomotion and a reduction of the extrusion of pseudopods on the surface of leukocytes, at the range of assayed concentrations. This inhibitory activity is probably derived from 2-deoxyribose.

Antigens↗
PubMed1984

Cellular immune response in liver of patients with chronic hepatitis B. Electron microscopic observation of lymphocyte subsets by the immunoperoxidase method using monoclonal antibodies.

The morphological association between lymphocytes and hepatocytes was studied at the light and electron microscopic levels by the peroxidase-labeled antibody method using mouse monoclonal antibodies against Leu-1, Leu-2a, Leu-3a, Leu-7 and Leu-10 antigens in liver biopsy specimens from patients with chronic hepatitis B. Leu-1 + cells (T cells), especially Leu-2a + cells (cytotoxic/suppressor T cells), infiltrated mostly in periportal areas with piecemeal necrosis and in parenchymal areas with focal necrosis. By double staining techniques, Leu-2a + cells were often seen in contact with hepatocytes containing membranous hepatitis B surface and/or core antigens in patients with chronic active hepatitis. At the ultrastructural level, Leu-2a + cells frequently occupied the sinusoid and also migrated into both the space of Disse and between hepatocytes. Furthermore, they often showed intimate surface-contact with hepatocytes having hepatitis B surface and/or core antigens, and, occasionally, injured hepatocytes were surrounded by several Leu-2a + cells. In contrast, Leu-3a + cells, Leu-7 + cells and Leu-10 + cells sometimes appeared in the sinusoid, but seldom in the space of Disse and between hepatocytes. These findings suggest that cytotoxic T lymphocytes may be associated with the necrosis of hepatocytes in chronic hepatitis B.

Antibodies, Monoclonal↗
PubMed1984

Occurrence of galactosamine-6-phosphate as a constituent of Bacillus megaterium spore coat.

Galactosamine-6-phosphate was identified as a component of the coat of the Bacillus megaterium QM B1551 spore. It was one of the main constituents of the outermost layer of the spore coat, but it was absent from the other integuments including the cortex. These findings suggest that galactosamine-6-phosphate comprises the phosphorus-containing skeleton structure of the spore coat.

Bacillus megaterium↗
PubMed1984

Monoclonal IgM-secreting neoplasms. Clinical and morphologic heterogeneity.

Two patients with monoclonal IgM-secreting neoplasms are presented. Though both patients could be diagnosed as Waldenström's macroglobulinemia, the clinicopathologic features were quite contrastive. Most neoplastic cells in Case 1 showed lymphocytic morphology with rather leukemic process, while those in Case 2 were highly polymorphic with solid proliferation. The clinical and morphologic heterogeneity in these cases and cases in the literature is discussed, and the possible requirement to establish a system for the subclassification of IgM-secreting neoplasms is insisted.

Antibodies, Monoclonal↗
PubMed1984

Clinical and histological features of sporadic non-A, non-B hepatitis.

The incidence of hepatitis A (HA), hepatitis B (HB), and non-A, non-B hepatitis (NANBH) was 27%, 30% and 43% among 73 patients with sporadic hepatitis. Epidemiological data (geographical distribution, seasonal variation, age, sex, and occupation) were not distinguishing of the type of hepatitis. Neither intrafamilial infection nor previous contact with viral hepatitis patients could be demonstrated in the NANBH cases. Fever and jaundice were less frequent in NANBH than in HA. Maximum levels of SGPT, serum bilirubin, ZTT, and gamma-globulin were significantly lower in NANBH than in HA and HB. Ten of 29 NANBH patients (35%) presented abnormal SGPT activities for more than 6 months, and four (14%) more than 12 months. In the ten patients with prolonged courses, jaundice was more frequent and maximum levels of SGPT were higher than in patients with transient courses. Histopathologic findings were not markedly different from those of HA and HB. Bile duct damage, fatty deposition, and giant multi-nucleated cells were recognized in 6, 12, and 2 NANBH patients, respectively. There were no characteristic ultrastructural changes in NANBH.

Adolescent↗
PubMed1984

Non-B hepatocellular carcinoma: influence of age, sex, alcohol, family clustering, blood transfusion and chronic liver disease.

In 144 cases of hepatocellular carcinoma (HCC), 166 cases of cirrhosis without HCC and 142 cases of chronic hepatitis, we examined HBsAg, anti-HBs and anti-HBc in sera and compared the following factors between hepatitis B virus marker-negative and -positive patients: age, sex, alcohol consumption, family clustering of liver diseases, and histories of blood transfusion and post-transfusion hepatitis. Results of this study demonstrated several distinct differences in clinical backgrounds between non-B (negative for HBsAg, anti-HBs and anti-HBc) and B (positive for HBsAg) patients with HCC. Non-B patients were significantly older, had a lower frequency of familial tendencies for liver diseases, and more frequently had cancers other than HCC in their families. Some of these differences were also observed between non-B and B patients with cirrhosis and chronic hepatitis. Among patients with chronic hepatitis, the non-B patients had received blood transfusion or had post-transfusion hepatitis more frequently than the B patients. However, this difference was not apparent in patients with liver cirrhosis or HCC, suggesting that progression of non-A, non-B post-transfusion hepatitis to cirrhosis and HCC may not be as frequent as progression to chronic hepatitis.

Age Factors↗
PubMed1983

Radioiodination studies of the envelopes from Xenopus laevis eggs.

To investigate the molecular basis of the observed morphological and biological characteristics of coelomic egg envelopes (CE), vitelline envelopes (VE), and fertilization envelopes (FE) of Xenopus laevis eggs, envelopes were radioiodinated under a variety of conditions: in situ, isolated and intact, or solubilized. The distribution of 125I in envelope components was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Each envelope type displayed unique profiles when iodinated in the intact state. A major constituent of VE, the 41,500 molecular weight component, was not labeled in the intact state, although the corresponding component of CE was heavily labeled. After dissociation of the envelope by guanidine-HCl or sodium dodecyl sulfate, all of the components could be radioiodinated. However, when the envelopes (VE and FE) were dissolved by heating and subsequently radioiodinated by lactoperoxidase, the resulting radioactivity profile was similar to that of the intact envelopes, suggesting that in the heat-dissolved envelope, the individual components retain similar structural relations as in the intact envelope. Quantitative but not qualitative differences were found between the inner and outer aspects of VE and FE. The significance of these findings is discussed in relation to what is known about the morphological, biological, and molecular properties of the envelopes.

Animals↗
PubMed1983

Intrahepatic distribution of T cell and T cell subsets in cases with type B chronic liver disease by peroxidase-labeled antibody method using monoclonal antibodies.

Intrahepatic distribution of T cell and T cell subsets was studied in 23 cases with type B chronic liver disease (of which 19 cases were also positive for hepatitis B e antigen) and in 6 cases with non-B chronic liver disease by indirect peroxidase-labeled antibody method using monospecific anti-T antibodies and other reagents (anti-Leu series). Hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in liver tissue were also observed by the peroxidase-labeled antibody method. Membranous expression of HBsAg was found in 16 out of 23 patients with sero-HBsAg, and HBcAg was detected in 15 of them. In these patients, pan-T cells (Leu-1 positive cells) were the predominant cells in the portal tract and the parenchyma. Particularly, T cytotoxic/suppressor cells (Leu-2a positive cells) were often recognized both in sites of piecemeal necrosis and focal necrosis. In some patients whose liver biopsy specimens were obtained during acute exacerbation of chronic hepatitis, T cytotoxic/suppressor cells as well as pan-T cells were increased remarkably in sites of piecemeal necrosis and focal necrosis. These results suggest that T cell cytotoxicity may play an important role in the pathogenesis of liver cell necrosis in type B chronic liver disease.

Chronic Disease↗
PubMed1983

Prolymphocytic leukemia with IgM hypogammaglobulinemia.

A case of prolymphocytic leukemia with IgM hypogammaglobulinemia in a 47-year-old man was presented. The leukemic cells possessed Ia-like antigen and receptors for the third component of complement but lacked surface immunoglobulins, cytoplasmic IgM, receptors for sheep red blood cells, or terminal deoxynucleotidyl transferase activity. In vitro immunoglobulin production experiments demonstrated that the leukemic cells did not have the capacity to produce IgM, while patient's T cells were shown to possess helper function on normal B cells to produce immunoglobulins. By these findings, together with the presence of selective IgM hypogammaglobulinemia, it was suggested that the leukemic cells were derived from a B-cell clone of a stage in differentiation and maturation of IgM-forming B-cell spectrum.

Cytoplasm↗